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101.
102.
Yan Yin Yang BiSongjiang Chen Yongcai LiYi Wang Yonghong GeBo Ding Yingchao LiZhong Zhang 《Scientia Horticulturae》2011
In order to understand the cuticular wax properties of Asian pear fruits (cv. Pingguoli), a series of assays was conducted on extraction, fractionation and determination of composition. The results showed that the maximum yield of wax from the fruit was obtained by chloroform/methanol (3:1), and then by chloroform extraction. Polar and low polar fractions occupied 64.3% and 26.9% of total crude wax by column chromatography. 54 and 22 components were identified in polar and low polar fractions by GC/MS, respectively. Long-chain fatty acids and triterpenoids predominated in polar fraction and n-alkanes were predominant in low polar fraction. In vitro tests indicated that polar fraction, low polar fraction and total crude wax inhibited spore germination and mycelial growth of Alternaria alternata, which is a causal agent of Alternaria rot of pears, and the maximum inhibition was obtained by polar fraction. These findings indicated that n-alkanes in low polar fraction and triterpenoids, fatty acid in polar fraction might have contributed to the antifungal properties of pear fruit cuticular waxes. 相似文献
103.
Summary In an X-ray diffraction investigation, the recrystallization behavior of ball-milled Chinese southern pine wood was found to differ from that of cellulose. The crystallinity of lignocellulose milled for a very long time and recrystallized by wetting in water did not decrease with increasing milling time as was the case with milled cellulose. In addition, it appeared that the presence of lignin tended to restrict the amorphous cellulose produced by milling from recrystallizing into Cellulose II, whereas it had no influence on the recrystallization into Cellulose I. These results were discussed in the context of the mechanism of the conversion of Cellulose I to Cellulose II. 相似文献
104.
天台黄山松种子园土壤肥力评价与改良措施 总被引:2,自引:0,他引:2
分析结果表明,天台华顶林场黄山松种子园土壤肥力平均水平中等偏下,尤其是有机质和的含量偏低,而氮的含量与针叶叶绿素的含量密切相关,为促进黄山松植株的生长,该种子园在加强水平带整修,开好竹节沟保水保土的同时,应着重套种绿肥,增施土杂肥,施化肥则以N.P.K混合肥或复合肥为好。 相似文献
105.
In production industry ofAuricularia auricular, the varieties quality is most important impact factor on output. For evaluating the early quality of the edible fungus,
9 varieties ofAuricularia auricular (Au9, CF09, CF05, 29, 916, chang10, chang7, Au.Japanese and 8808) were cultured on the medium consists of potato dextrose
agar (PDA) and sawdust to test their mycelium growth rate, endurance to high temperature, resistance to mildew, assimilation
of nutriment, and resistance to drought. The result showed that the mycelium of Chang 10, CF09, 29 and Au.Japanese varieties
had the eminent characteristics such as short lifespan, stronger assimilation of nutriment, and endurance to high temperature
and steady growth. These four varieties are determined as superiority varieties ofAuricularia auricular in accordance with the research results.
Foundation item: The research was supported by Science Fund of Northeast Forestry University (2004).
Biography: Li Ling (1964-), female, Engineer in Northeast Forestry University, Harbin 150040, P. R. China.
Responsible editor: Zhu Hong 相似文献
106.
在含Ag~+浓度为0.1~2.0ppm的屠宰废水中,凤眼莲降低N、P元素的效率,随浓度增加而降低;当Ag~+浓度为2ppm时,凤眼莲降低N、P元素的效率,随处理时间的延长而增加。去除N的百分率低于P的百分率。屠宰废水中的Ag~+浓度高达15ppm时,凤眼莲植株在24小时内坏死。不同Ag~+浓度的废水对凤眼莲根系脱氢酶活力水平的影响大小不同,从而影响到N、P元素的去除效率。实验结果为利用凤眼莲净化屠宰废水,富集回收水环境中的银,提供了重要依据。 相似文献
107.
108.
阐述交通冲突的基本概念和技术方法.阐明交通冲突技术的优越性,分析国内外交通冲突技术的研究现状及存在问题,在理论和工程应用两方面,提出交通冲突技术进一步研究的一些看法或设想。 相似文献
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110.